When you create an item with the CanPlaceOn or CanDestroy tag, like this:

/give @p log 1 1 {CanPlaceOn:["standing_sign"]}

It won't show
Can be placed on:
Standing Sign

It just shows
Can be placed on:
Sign
(Which is when you want to be precise, incorrect because you can't place it on a wall_sign then)

Same for

• banners
• repeaters (powered/unpowered)
• redstone lamps (on/off)
• comparators (powered/unpowered)
• furnace (lit/unlit)
• redstone torch (lit/unlit)
• redstone ore (lit/normal)
• daylight sensor (inverted/normal)
• Mushroom (brown/red)
• Flowers (yellow/red)